Structural assessment, maintenance, and repair apparatuses and methods

ABSTRACT

Systems for cleaning a structure via a robot are described. The robot includes a body. The robot further includes a tool coupled to the body and configured to hold a structural maintenance tool. The robot includes a sensor coupled to the body. The robot includes a drive system configured to allow positioning of the body along the structure, including inverted positioning and vertical positioning. The robot further includes a communication interface coupled to the body. The robot includes a controller coupled to the body. The controller is in communication with the tool, the sensor, and the drive system. The controller is configured to receive an operating instruction through the communication interface. The controller is configured to autonomously position the body via the drive system and to perform a task with at least one of the tool and the sensor according to the operating instruction.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a continuation of application Ser. No. 14/090,725,filed Nov. 26, 2013, and is a continuation of application Ser. No.14/091,150, filed Nov. 26, 2013, both of which are incorporated byreference in their entireties.

BACKGROUND

Large structures, such as buildings, bridges, and oil rigs, requireregular maintenance and inspection. Typically, regular inspection andmaintenance is performed by human crews. However, human crews havephysical limits and may be expensive to employ. For example, reachingcertain areas of the structures, such as the top trusses and underwatersupports of a bridge, may be difficult and dangerous for humaninspection and maintenance crews. Further, some areas of structures,including tight spaces, may be completely inaccessible by humaninspection and maintenance crews. Still further, human inspection andmaintenance crews are susceptible to inclement weather conditions, whichmay hamper and delay maintenance and inspection operations.

SUMMARY

The foregoing summary is illustrative only and is not intended to be inany way limiting. In addition to the illustrative aspects, embodiments,and features described above, further aspects, embodiments, and featureswill become apparent by reference to the drawings and the followingdetailed description.

One embodiment relates to a system for maintaining a structure. Thesystem includes a first robot. The first robot includes a first robotbody, a first robot tool arm coupled to the first robot body, a firstrobot sensor coupled to the first robot body, a first robot drive systemconfigured to allow positioning of the first robot along the structure,including inverted positioning and vertical positioning, a first robottransceiver coupled to the first robot body, and a first robotcontroller coupled to the first robot body. The system further includesa second robot. The second robot includes a second robot body, a secondrobot drive system configured to allow positioning of the second robotalong the structure, a second robot transceiver coupled to the secondrobot body, and a second robot controller coupled to the second robotbody. The system includes a base station in communication with the firstrobot via the first robot transceiver and/or in communication with thesecond robot via the second robot transceiver. The first robot isconfigured to autonomously perform a maintenance task on the structure.The second robot is configured to autonomously provide a support serviceto the first robot during the maintenance task. The first robot isconfigured to communicate with the second robot.

Another embodiment relates to a method of performing a maintenance taskon a structure via a robot. The method includes moving to an area of thestructure through a drive system of the robot. The method furtherincludes detecting a characteristic of a portion of the structurethrough a sensor of the robot, and, in response to detecting thecharacteristic, identifying a maintenance task. The method includesperforming the maintenance task through a tool mounted to a tool arm ofthe robot. The method further includes documenting the performance ofthe maintenance task.

Still another embodiment relates to a method of painting a structure viaa robot. The method includes receiving a command to paint at least aportion of the structure via a transceiver of the robot. The methodfurther includes analyzing the command via a controller of the robot,wherein the analyzing includes identifying the portion of the structurewhere painting is to be performed. The method includes moving to theportion of the structure through a drive system of the robot. The methodfurther includes identifying a first area of the portion of thestructure as a target for painting. The method includes determining thata second area proximate the structure is not occupied by an objectthrough a sensor of the robot, wherein the second area of the structureis at risk of being hit by an overspray of paint. The method includes,after determining that the second area proximate the structure is notoccupied by the object, painting the first area of the structure througha tool of the robot.

Yet another embodiment relates to a method of detecting and repairingcorrosion on a structure via a robot. The method includes receiving acommand to locate and repair corrosion on the structure through atransceiver of the robot. The method further includes analyzing thecommand through a controller of the robot. The method includes roving toan area of the structure. The method further includes identifying, via afirst sensor of the robot, an area of corrosion on the structure. Themethod includes cleaning the area with an abrasive tool mounted to therobot. The method further includes, after cleaning the area, paintingthe area with a painting tool of the robot.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of a bridge having maintenance robots according to anembodiment.

FIG. 2 is a view of a robot according to an embodiment.

FIG. 3 is a view of a robot according to an embodiment.

FIG. 4 is a view of a robot according to an embodiment.

FIG. 5 is a view of a robot according to an embodiment.

FIG. 6 is a block diagram of a controller for a robot according to anembodiment.

FIG. 7 is a flow diagram of a method of performing a function via arobot is shown according to an embodiment.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof. In the drawings,similar symbols typically identify similar components, unless contextdictates otherwise. The illustrative embodiments described in thedetailed description, drawings, and claims are not meant to be limiting.Other embodiments may be utilized, and other changes may be made,without departing from the spirit or scope of the subject matterpresented here.

Referring to FIG. 1, bridge 100 is shown according to one embodiment.Bridge 100 includes above water portions 101 and below water portions102. A number of robots 103 are shown on bridge 100. Robots 103 affix tobridge 100 and move about bridge 100. Robots 103 affix to bridge 100through various methods, including, but not limited to, suction devices,dry adhesives, adhesives, mechanical grippers, magnetism,electroadhesion, treads, and wheels. Some robots 103 may be configuredfor underwater use, in which case robots 103 include underwaterpropulsion mechanisms such as propellers and/or water jets. Robots 103are equipped with sensors and tools such that robots 103 canautonomously inspect, clean, and/or repair bridge 100 depending on thetool configuration and received programming instructions. The tools andsensors may be mounted to tool arms or to the body of each robot 103.The tools and sensors may be removably mounted to the tool arms and/orto the body of each robot such that the tools and sensors arereplaceable. In such an arrangement, robots 103 are reconfigurable fordifferent tasks. Robots 103 may communicate (e.g., wirelessly) withother robots and/or with a base station (e.g., a control vehicle havinghuman operators, a fixed control facility, etc.). Robots 103 may come ina variety of sizes and may be used to inspect a variety of structures.The details of robots 103 are discussed in further detail below.

Referring to FIG. 2, robot 200 is shown according to one embodiment.Robot 200 includes main body 201. Main body 201 may be constructed frommetal (e.g., steel, aluminum, titanium, or alloys thereof), plastics,composites (e.g., fiberglass, carbon fiber, etc.), or a combinationthereof. The various components of robot 200 are coupled to main body201. Robot 200 is shown as having four legs 202. In alternativearrangements, robot 200 may include a different number of legs 202(e.g., six legs, eight legs, ten legs, etc.). In the embodiment of FIG.2, each leg 202 includes three joints 203, 204, and 205, which enablemovement of the various parts of leg 202. Joints 203, 204, and 205 maybe universal joints that allow for three axes of movement. Each joint203, 204, and 205 includes at least one motor (e.g., a servo motor) forcontrolled relative movement of parts of leg 202 about joints 203, 204,and 205.

In the embodiment of FIG. 2, each leg 202 includes surface grippingelement 206. Element 206 is coupled to leg 202. Element 206 isconfigured to removably affix robot 200 to a surface of a structure(e.g., a beam of bridge 100) such that robot 200 can move alongstructures having a steep incline, vertical structures (e.g., a verticalbeam of bridge 100, a wall of a building, etc.), or in an invertedmanner (along the underside of bridge 100, on the ceiling of a building,etc.). Accordingly, element 206 creates an attraction force betweenelement 206 and a surface.

The attraction force may be achieved using a variety of techniques. Insome arrangements, element 206 includes a dry adhesive. A dry adhesiveuses microscopic setae and spatulae that, when pressed directly into asurface, create an adhesion force capable of supporting a load on avertical surface. Further details of how dry adhesives function can befound in U.S. Pat. No. 8,398,909 to Sitti et al., entitled “DRYADHESIVES AND METHODS OF MAKING DRY ADHESIVES,” dated Mar. 19, 2013. Inother arrangements, element 206 may include a suction device. In such anarrangement, a vacuum creates a controllable suction force such thatelements 206 are selectively secured to a surface. The amount ofelectrical power provided to the vacuum may be increased or decreaseddepending on the amount of suction force required to secure element 206to the surface. In another arrangement, element 206 includes anelectromagnet. In such an arrangement, the electromagnet is selectivelypowered such that elements 206 are selectively secured to a surface viamagnetic force. The amount of electrical power provided to theelectromagnet may be increased or decreased depending on the magneticforce required to secure element 206 to the surface. In yet anotherarrangement, element 206 includes at least one electrode for creatingelectrostatic adhesion between element 206 and a surface. When powered,the electrode may pass electrons from element 206 to a conductivesurface (e.g., a steel beam of bridge 100), which creates anelectrostatic attractive force between element 206 and the surface. Inanother arrangement, element 206 includes a mechanical grippingappendage designed to grasp the surface (e.g., by at least partiallyencircling it, by inserting screws or pitons, etc.). In anotherarrangement, element 206 includes a combination of any of the above theabove described gripping mechanisms (e.g., a suction mechanism, a dryadhesive, a mechanical gripper, and an electromagnet).

Robot 200 includes arms 207. Arms 207 are similar to legs 202. Althoughrobot 200 is drawn as having two arms 207, it should be understood thatany number of arms may be used (e.g., one arm, three arms, four arms,etc.). Further, arms may be mounted to any side of body 201. Arms 207include joints 208, 209, and 210. Joints 208, 209, and 210 may beuniversal joints that allow for three axes of movement. Each joint 208,209, and 210 includes at least one motor (e.g., a servo motor) forcontrolled relative movement of parts arm 207 about joints 208, 209, and210. Each arm 207 includes tool connector 211. Tool connector 211 isconfigured to removably receive a variety of tools (e.g., a welder, abrush, a hammer, a drill, shears, a fastener driver, a paint sprayer, anabrasive blaster, etc.) and/or sensors (ultrasound sensors, x-raysensor, stress sensors, cameras, acoustic sensors, etc.) in aninterchangeable manner. Accordingly, robot 200 can be configured toperform a variety of tasks, such as structure inspection, structurecleaning, structure painting, and structure repair. Tool connector 211may be a proprietary connector.

Robot 200 also includes additional components coupled to body 201. Insome arrangements, robot 200 includes solar panel 212 coupled to body201. Solar panel 212 provides operational power to robot 200 and/orcharges batteries within body 201. In certain arrangements, light 213 iscoupled to body 201. Light 213 illuminates a workspace of robot 200during dimly lit or nighttime operations. Light 213 may providespectrally defined illumination, having specified colors or spectralbands (infrared, visible, ultraviolet) selected to improve imaging of afeature needing maintenance (e.g., a corroded portion of the surface),or of the maintenance progress (e.g., detection of a paint or surfacetreatment). Light 213 may provide multi-spectral light or polarizedlight for multi-spectral imaging or polarized imaging of a component ofthe structure. Light 213 assists robot 200 with low-light image andvideo capturing through camera 214. Camera 214 is coupled to body 201.In alternative arrangements, camera 214 may be coupled to tool connector211 of an arm 207. In some configurations, robot 200 includes multiplecameras, which enable stereoscopic three-dimensional image and videocapture.

Referring to FIG. 3, robot 300 is shown according to one embodiment.Robot 300 is similar to robot 200. Robot 300 includes main body 301.Main body 301 may be constructed from metal (e.g., steel, aluminum,titanium, or alloys thereof), plastics, composites (e.g., fiberglass,carbon fiber, etc.), or a combination thereof. The various components ofrobot 300 are coupled to main body 301. Unlike robot 200, robot 300 doesnot include legs. Instead, robot 300 includes wheels 302. Although robot300 is shown as including four wheels, robot 300 may include threewheels or more than four wheels.

Each wheel 302 includes a plurality of surface gripping elements 303.Element 303 is coupled to leg 202. Elements 303 are configured toremovably affix robot 300 to a surface of a structure (e.g., a beam ofbridge 100) such that robot 300 can move along structures having a steepincline, vertical structures (e.g., a vertical beam of bridge 100, awall of a building, etc.), or in an inverted manner (along the undersideof bridge 100, on the ceiling of a building, etc.). Accordingly,elements 303 create an attraction force between elements 303 and asurface.

The attraction force may be achieved using a variety of techniques.Elements 303 may include the same components as discussed above withelements 206. Accordingly, elements 303 may include a dry adhesive, asuction mechanism, a mechanical gripper, an electromagnet, at least oneelectrode for creating electrostatic adhesion between element 303 and asurface, or a combination of the above the above described grippingmechanisms (e.g., a suction mechanism, a dry adhesive, and anelectro-magnet).

In the embodiment of FIG. 3, robot 300 includes arms 304. Arms 304 aresimilar to arms 207 of robot 200. Although robot 300 is drawn as havingtwo arms 304, it should be understood that any number of arms may beused. Further, arms may be mounted to any side of body 301. Arms 304include joints 305, 306, and 307. Joints 305, 306, and 307 may beuniversal joints that allow for three axes of movement. Each joint 305,306, and 307 includes at least one motor (e.g., a servo motor) forcontrolled relative movement of parts arm 304 about joints 305, 306, and307. Each arm 304 includes tool connector 308. Tool connector 308 isconfigured to removably receive a variety of tools (e.g., a welder, abrush, a hammer, a drill, shears, a fastening driver, paint sprayer,sandblaster, etc.) and/or sensors (ultrasound sensors, x-ray sensor,stress sensors, cameras, acoustic sensors, etc.) in an interchangeablemanner. Accordingly, robot 300 can be configured to perform a variety oftasks, such as structure inspection, structure cleaning, structurepainting, and structure repair. Tool connector 308 may be a proprietaryconnector.

Robot 300 also includes additional components coupled to body 301. Incertain arrangements, light 309 is coupled to body 301. Light 309illuminates a workspace of robot 300 during dimly lit or nighttimeoperations. Light 309 may provide spectrally defined illumination,having specified colors or spectral bands (infrared, visible,ultraviolet) selected to improve imaging of a feature needingmaintenance (e.g., a corroded portion of the surface), or of themaintenance progress (e.g., detection of a paint or surface treatment).Light 309 may provide multi-spectral light or polarized light formulti-spectral imaging or polarized imaging of a component of thestructure. Light 309 assists robot 300 with low-light image and videocapturing through camera 310. Camera 310 is coupled to body 301. Inalternative arrangements, camera 310 may be coupled to tool connector308 of an arm 304. In some configurations, robot 300 includes multiplecameras, which enable stereoscopic three-dimensional image and videocapture.

Referring to FIG. 4, robot 400 is shown according to one embodiment.Robot 400 is similar to robots 300 and robot 200. Robot 400 includesmain body 401. Main body 401 may be constructed from metal (e.g., steel,aluminum, titanium, or alloys thereof), plastics, composites (e.g.,fiberglass, carbon fiber, etc.), or a combination thereof. The variouscomponents of robot 400 are coupled to main body 401. Unlike robots 200or 300, robot 400 is propelled by driven track 402. Robot 400 includesany number of tracks 402 (e.g., one track, two tracks, three tracks,etc.).

In the embodiment of FIG. 4, each track 402 includes a plurality ofsurface gripping elements 403 coupled to tracks 402. Elements 403 areconfigured to removably affix robot 400 to a surface of a structure(e.g., a beam of bridge 100) such that robot 400 can move alongstructures having a steep incline, vertical structures (e.g., a verticalbeam of bridge 100, a wall of a building, etc.), or in an invertedmanner (along the underside of bridge 100, on the ceiling of a building,etc.). Accordingly, elements 403 create an attraction force betweenelements 403 and the surface that robot 400 is moving along.

The attraction force may be achieved using a variety of techniques.Elements 403 may include the same components as discussed above withelements 206 and 303. Accordingly, elements 403 may include a dryadhesive, a suction mechanism, a mechanical gripper, an electromagnet,at least one electrode for creating electrostatic adhesion betweenelement 403 and a surface, or a combination of the above the abovedescribed gripping mechanisms (e.g., a suction mechanism, a dryadhesive, and an electro-magnet).

In some configurations, robot 400 includes adhesive dispensers 404 andadhesive scrapers 405. Adhesive dispensers 404 spray adhesive 406 onto asurface robot 400 is traversing. The adhesive may be sprayed between thesurface of the structure and a component of the robot drive system(e.g., between track 402 and the structure). The adhesive works toadhere robot 400 to the surface. The adhesive may be a drying adhesive,a pressure sensitive adhesive, a contact adhesive, a hot adhesive, amulti-part reactive adhesive (e.g., epoxy), or a one-part reactiveadhesive. Scrapers 405 are movable such that scrapers only scrape thesurface when instructed. Scrapers 405 can be lowered to touch thesurface such that sprayed adhesive 406 is scraped off of the surface.Dispensers 404 and scrapers 405 are provided on both sides of tracks 402to facilitate both forwards and backwards motion of robot 400 duringinclined, vertical, or inverted movement. Adhesive 406 may be used tosupplement the attractive forces provided by elements 403 or may be usedin place of elements 403.

Robot 400 includes arms 407. Arms 407 are similar to arms 207 and 304 ofrobots 200 and 300. Although robot 400 is drawn as having two arms 407,it should be understood that any number of arms may be used. Further,arms may be mounted to any side of body 401. Arms 407 include joints408, 409, and 410. Joints 408, 409, and 410 may be universal joints thatallow for three axes of movement. Each joint 408, 409, and 410 includesat least one motor (e.g., a servo motor) for controlled relativemovement of parts arm 407 about joints 408, 409, and 410. Each arm 407includes tool connector 411. Tool connector 411 is configured toremovably receive a variety of tools (e.g., a welder, a brush, a hammer,a drill, shears, a fastening driver, paint sprayer, sandblaster, etc.)and/or sensors (ultrasound sensors, x-ray sensor, stress sensors,cameras, acoustic sensors, etc.) in an interchangeable manner.Accordingly, robot 400 can be configured to perform a variety of tasks,such as structure inspection, structure cleaning, structure painting,and structure repair. Tool connector 411 may be a proprietary connector.

Robot 400 also includes additional components coupled to body 401. Incertain arrangements, light 412 is coupled to body 401. Light 412illuminates a workspace of robot 400 during dimly lit or nighttimeoperations. Light 412 may provide spectrally defined illumination,having specified colors or spectral bands (infrared, visible,ultraviolet) selected to improve imaging of a feature needingmaintenance (e.g., a corroded portion of the surface), or of themaintenance progress (e.g., detection of a paint or surface treatment).Light 412 may provide multi-spectral light or polarized light formulti-spectral imaging or polarized imaging of a component of thestructure. Light 412 assists robot 400 with low-light image and videocapturing through camera 413. Camera 413 is coupled to body 401. Inalternative arrangements, camera 413 may be coupled to tool connector411 of an arm 407. In some configurations, robot 400 includes multiplecameras, which enable stereoscopic three-dimensional image and videocapture.

Referring to FIG. 5, robot 500 is shown according to one embodiment.Robot 500 is similar to robots 200, 300, and 400. However, robot 500 isadditionally configured for operation underwater. Robot 500 includesmain body 301. Main body 501 may be constructed from metal (e.g., steel,aluminum, titanium, or alloys thereof), plastics, composites (e.g.,fiberglass, carbon fiber, etc.), or a combination thereof. The variouscomponents of robot 500 are coupled to main body 501. Main body 501 maybe water-tight to protect internal components. Alternatively, body 501includes a separate water-tight compartment for housing electricalcomponents (e.g., a controller, a transceiver, a battery, etc.). Robot500 includes multiple movement mechanisms to allow robot 500 to moveover ground, across structures, and underwater. Robot 500 includes atransceiver configured for communications with an external base station(located either above the water surface, or underwater). Thecommunication between robot 500 and the extern base station may be via acable (e.g., an optical fiber), or may be wireless (e.g., acoustic).

Robot 500 includes two tracks 502, which provide robot 500 movement overland and across structures. Although drawn as including two tracks 502,robot 500 can include any number of tracks. Each track 502 includes aplurality of surface gripping elements 503 coupled to tracks 502.Elements 503 are configured to removably affix robot 500 to a surface ofa structure (e.g., a beam of bridge 100) such that robot 500 can movealong structures having a steep incline, vertical structures (e.g., avertical beam of bridge 100, a wall of a building, etc.), or in aninverted manner (along the underside of bridge 100, on the ceiling of abuilding, etc.). Accordingly, elements 503 create an attraction forcebetween elements 503 and a surface.

The attraction force may be achieved using a variety of techniques.Elements 503 may include the same components as discussed above withelements 206, 303, and 403. Accordingly, elements 503 may include a dryadhesive, a suction mechanism, a mechanical gripper, an electromagnet,at least one electrode for creating electrostatic adhesion betweenelement 503 and a surface, or a combination of the above the abovedescribed gripping mechanisms (e.g., a suction mechanism, a dryadhesive, and an electro-magnet).

Robot 500 further includes an underwater drive system having motorizedpropeller 504. Propeller 504 is mounted on rudder 505. Propeller 504 isrotated about main body 501 to propel robot 500. Propeller 504 can bepowered in both directions to cause forward and backward movement ofrobot 500 underwater. To assist with underwater navigation, robot 500further includes elevator fins 506 and ballast 507. Elevator fins 506can be rotated with respect to body 501 to help robot 500 ascend ordescend while underwater. Ballast 507 can fill with air or liquid toadjust the buoyancy of robot 500. Accordingly, ballast 500 assists robot500 in ascending or descending while underwater. Robot 500 also includeswater jets 508. Water jets 508 are individually operable. Each water jet508 can propel a jet of water. Accordingly, water jets 508 assist robot500 in ascending or descending while underwater. Robot 500 may becapable of navigation through liquids other than water, such as oil.

Further referring to FIG. 5, robot 500 includes arms 509. Arms 509 aresimilar to arms 207, 304, and 407. Although robot 500 is drawn as havingtwo arms 509, it should be understood that any number of arms may beused. Further, arms may be mounted to any side of body 501. Arms 509include joints 510, 511, and 512. Joints 510, 511, and 512 may beuniversal joints that allow for three axes of movement. Each joint 510,511, and 512 includes at least one motor (e.g., a servo motor) forcontrolled relative movement of parts arm 509 about joints 510, 511, and512. Each arm 509 includes tool connector 513. Tool connector 513 isconfigured to removably receive a variety of tools (e.g., a welder, abrush, a hammer, a drill, shears, a fastening driver, paint sprayer,sandblaster, etc.) and/or sensors (ultrasound sensors, x-ray sensor,stress sensors, cameras, acoustic sensors, etc.) in an interchangeablemanner. Accordingly, robot 500 can be configured to perform a variety oftasks, such as structure inspection, structure cleaning, structurepainting, and structure repair. Tool connector 513 may be a proprietaryconnector.

Robot 500 also includes additional components coupled to body 501. Incertain arrangements, light 514 is coupled to body 501. Light 514illuminates a workspace of robot 500 during dimly lit or nighttimeoperations. Light 514 may provide spectrally defined illumination,having specified colors or spectral bands (infrared, visible,ultraviolet) selected to improve imaging of a feature needingmaintenance (e.g., a corroded portion of the surface), or of themaintenance progress (e.g., detection of a paint or surface treatment).Light 514 may provide multi-spectral light or polarized light formulti-spectral imaging or polarized imaging of a component of thestructure. Light 514 also assists robot 500 with low-light image andvideo capturing through camera 515. Camera 515 is coupled to body 501.In alternative arrangements, camera 515 may be coupled to tool connector513 of an arm 509. In some configurations, robot 500 includes multiplecameras, which enable stereoscopic three-dimensional image and videocapture.

The machines described in FIG. 2 through FIG. 5 above provide fourdevices that may be used for structure inspection, cleaning, and/orrepair. However, it should be understood that alternatively configuredrobots may be used within the scope of the contemplated invention. Forexample, any number and combination of tool arms, cameras, sensorarrays, and movement mechanisms may be employed.

Referring to FIG. 6, a block diagram of controller 600 is shownaccording to an embodiment. Controller 600 may be used to control theoperation of any of the above discussed robots (i.e., robot 200, robot300, robot 400, or robot 500) or a similarly configured robot.Controller 600 includes processor 601 and memory 602. Memory 602 storesprogramming instructions that, when executed by processor 601, controlthe robot's operation, including the various components of the robot.Controller 600 is in electrical communication with drive system 603, arm604, tool 605, sensor 606, camera 607, and light 608. As discussed abovewith respect to robots 200, 300, 400, and 500, a robot may have aplurality of any of drive systems, arms, tools, sensors, cameras, andlights. In such arrangements, controller 600 is in electricalcommunication with each of the plurality of components.

Controller 600 includes wireless transceiver 609. Wireless transceiver609 may be integrated into controller 600 (e.g., controller may be asystem-on-chip including processor 601, memory 602, and wirelesstransceiver 609 on a single chip) or a separate component in electricalcommunication with controller 600. Controller 600 receives operatinginstructions from an outside source through wireless transceiver 609.For example, controller 600 can receive operating instructions from anoperator at a control station. The operating instructions may relate toremote control instructions (i.e., when the operator is controlling allof the functions of the robot) or autonomous operation instructions toperform a task with little or no operator intervention (e.g., autonomousinspections, autonomous repainting, autonomous repair, etc.). Stillfurther, controller 600 can communicate with other robots throughwireless transceiver 609. In some situations, robots are instructed towork together on the same or related tasks. Accordingly, the robots mayneed to communicate with each other. For example, a first robot may beinstructed to inspect a structure, and a second robot may be instructedto repair defects in the structure found by the first robot. In such aconfiguration, the first robot will transmit defect information (e.g.,type of defect, location of defect on the structure, defect repairstrategy, etc.) to the second robot. In some embodiments the first robotand the second robot may communicate with each other wirelessly (e.g.,via radio-frequency, acoustics, optics, etc.); in other embodiments theymay communicate via a cable (e.g., an optical fiber, a wire, coaxialcable, etc.). In some embodiments, a first robot may communication withan external base station via a wireless transceiver, such that the firstrobot may relay communications designated for the second robot from theexternal base station to the second robot, or may relay communicationsfrom the second robot to the external base station. As an additionalexample, a pair of robots can be used where a first robot performsassigned maintenance tasks (e.g., inspection and repair) and a secondrobot provides a support service to the first robot. The support servicemay include the carrying of supplies to be used by the first robot(e.g., additional tools, abrasives for sand blasting, paint forpainting, additional batteries for extended operation, etc.), assistingwith tool change operations for the first robot, charging the firstrobot's batteries through a charging port of the second robot, or asimilar ancillary task. In such a configuration, the first robot willtransmit requests to the second robot.

Controller 600 receives operational electrical power from power supply610. Power supply 610 provides to controller 600 and all components ofthe robot. Power supply 610 may be any suitable power source, including,but not limited to, a battery, a generator, a solar power source, gridpower, or a combination thereof. In arrangements where power supply 610includes a rechargeable battery, the battery may be charged duringoperation through another power source (e.g., a generator, a solarpanel, grid power, etc.) or through inductive charging (i.e., the robotcan drive over an inductive charger configured to charge therechargeable battery).

Referring to FIG. 7, method 700 of performing a function via a robot isshown according to an embodiment. Method 700 may be employed by any ofthe above described robots (i.e., robot 103, robot 200, robot 300, robot400, and/or robot 500) or another robot configured to inspect and/orperform repairs on a structure.

The robot receives operating instructions (701). Operating instructionsmay be received through a wireless transceiver of the robot. Theoperating instructions may originate from a base station (e.g., a humanoperator at the base station) or from another robot (e.g., during amulti-robot operation). After receiving the instructions, the robotanalyzes the operating instructions (702). The controller of the robotparses the received instructions to determine the individual tasks ofthe instructions, where the tasks are to be performed (e.g., what areaof the structure the robot should move to), and when the tasks are to beperformed. The instructions may relate to an on-demand task (e.g.,repainting a portion of a structure upon receipt of the instructions), ascheduled task (e.g., repainting a portion of a structure at adesignated time and date), or performing a task autonomously based onsensor results (e.g., repainting a portion of a structure based onsensor feedback indicating that the portion requires repainting).

After analyzing the instructions, the robot executes the operatinginstructions (703). The robot executes the instructions at the properlocation on the structure (e.g., by moving to the target location of thestructure) at the time of execution. The instructions can include anycombination of tasks, including, but not limited to: detecting, sensing,and analyzing features of the structure (704), painting (705), cleaning(706), crack dislocation, migration, or prevention (707), welding (708),performing a tool change (709), charging (710), and/or communicatingwith other robots (711). The above discussed tasks are discussed belowin greater detail.

Further referring to FIG. 7, the robot determines if the operatinginstructions have been completed (712). If the operating instructionshave not been completed, method 700 returns to 703 for continuedexecution of the operating instructions. If the operating instructionshave been completed, the robot sends a final report to the base station(713). In some embodiments, progress reports may be sent during therobot's operation. The report may include documentation of theperformance of the maintenance task, e.g., to demonstrate that it wassuccessfully performed. The report may include metadata, such as thetime at which a maintenance activity was performed or the location ofthe maintenance activity. The report may document the pre-maintenancestate of a site on the structure (e.g., to demonstrate the need for themaintenance, or to demonstrate that a site was inspected but did notrequire maintenance).

After sending the final report to the base station, the robot enters astandby state (714). Just prior to entering the standby state, the robotmay perform a pre-standby task, such as returning to a designatedlocation and/or performing a charging function. For example, the robotmay have standing instructions to return to a garage located on thestructure prior to entering the standby mode. The pre-standby modeinstructions may further include a charge command. The charge commandcan include parking the robot over an inductive charging port,instructing the robot to use a tool to plug into grid power, and/orpositioning the robot such that it can receive electrical power fromother sources (e.g., positioning the power such that built-in solarpanels receive sun light). During the standby state, the robot enters alow-power mode. During the low-power mode, the robot's wirelesstransceiver remains active such that the robot can receive additionaloperating instructions. The controller of the robot also is at leastpartially powered during the low-power mode such that the controller cansend and receive communications to and from the base station and/orother robots. Accordingly, if an instruction is received during thelow-power, standby mode, the robot reactivates and method 700 isrepeated.

In some embodiments, the robot is configured to operate autonomously. Itmay receive general operating instructions such as which area of astructure to examine, and which type of maintenance activities toperform. Alternatively, such instructions may be implicit e.g., therobot may be delivered to a structure via a truck, and then autonomouslyrove the structure, detecting areas in need of maintenance andperforming the maintenance as needed. In some embodiments, the types ofmaintenance to be carried out can be implicitly defined by the tools andsensors present on the robot. The robot's roving route can be predefinedbased on the structure, can be defined by local conditions or sets ofrules (e.g., always turn left, never repeat a section, etc.), can be arandom or quasi-random path, etc. The robot may continue its autonomousactivity for a defined amount of time, until a specified amount of thestructure has been covered, etc.

Still referring to FIG. 7, as noted above, the operating instructions tothe robot may include a variety of tasks and various combinations oftasks. The operating instructions may designate that multiple tasks areto be performed in a designated sequence. If multiple tasks are to beperformed, the tasks may be performed by multiple robots or a singlerobot. The details of the tasks and how the tasks are carried out viathe robots are described in further detail below.

The operating instructions may include an instruction for the robot toperform a detecting, sensing, and/or analyzing task (704). Thedetecting, sensing, and/or analyzing task may be for the purposes ofgenerating data sets to report back to the base station or for localanalysis by the controller of the robot (e.g., to determine whether ornot detected stresses exceed a designated safety threshold). Thedetecting, sensing, and/or analyzing may be for the purposes ofidentifying areas of the structure requiring maintenance, which may belater performed by the robot. For example, during the detecting,sensing, and or analyzing, the robot may identify an area of rustbuildup on the surface of the structure. After identifying the area, therust may be removed by a cleaning operation (e.g., step 706) and thenrepainted (e.g., during 705). To accomplish the detecting, sensing,and/or analyzing task, the robot is configured with a sensor or aplurality of sensors (as discussed above with respect to robot 200,robot 300, robot 400, and robot 500).

The robot may include a sensor or a plurality of sensors to measurecharacteristics and identify features of the structure. The robot may beequipped with an ultrasound transducer. In such an arrangement, thetransducer emits ultrasound waves into the structure, which at leastpartially reflect back towards the transducer for reception andanalysis. The controller of the robot analyzes the ultrasoundreflections. Localized structure stress levels, cracks, and otherimperfections may be identified based on variances in the ultrasoundreflections. The robot may be equipped with an eddy current sensor. Theeddy current sensor generates and analyzes multi-frequency signals todetermine localized structure stress levels, cracks, and otherimperfections. A discussion of the use of eddy current sensors toinspect materials can be found in U.S. Pat. No. 7,206,706 to Wang et al.entitled “INSPECTION METHOD AND SYSTEM USING MULTIFREQUENCY PHASEANALYSIS,” dated Apr. 17, 2007. The robot may be equipped with avibration sensor. The vibration sensor may be a piezo vibration sensor.The vibration sensor may be used to measure the vibration and resonancebehavior of the structure. The robot may be equipped with an x-raysensor configured to take x-ray images of the structure that may bebeneficial in locating stress levels, cracks, and other imperfection ofthe structure. The robot may be equipped with a stress sensor. Thestress sensor may be a resistive stress sensor that is temporarilyaffixed to a surface of the structure. The stress sensor may be used tomeasure compressive, tensile, and axial forces experienced by thestructure at the location where the sensor is placed.

Additionally, the robot may be equipped with environmental sensors tomeasure atmospheric weather conditions (e.g., temperature, air pressure,humidity, wind direction, wind speed, etc.). The environmental sensorsmay measure underwater conditions. For example, if the structure is abridge, an off-shore oil platform, or the like, the robot may be capableof underwater activities (e.g., robot 500). Accordingly, the robot maymeasure water temperature, water flow rate, and water flow direction. Itshould be understood that the sensors may measure non-water fluidcharacteristics. For example, a robot may be configured for operation ina non-water fluid (e.g., oil), and the sensors may measurecharacteristics of the non-water fluid.

The robot may be equipped with a camera. The camera may be mounted to anarticulating tool arm of the robot such that the camera can bepositioned to view different areas of the structure and of thesurrounding environment. The camera may be an infrared camera or avisible light camera. The camera may be a multi-spectral camera or apolarized camera. The robot may have multiple cameras capable offocusing on different locations and/or providing a stereoscopic view.The robot may take images and/or videos of the structure and thesurrounding environment. The images and/or videos may be processed bythe controller to identify features (e.g., cracks, corrosion,cars/trucks/trains/people using the structure, etc.). The images and/orvideos may be stored in a memory of the robot for later export ortransmission to a server or a base station. The images and/or videos maybe transmitted in a live or a near-live steam to a server or a basestation. The live or near-live stream may be used to assist in providinga remote control capability of the robot. The operating instructions mayinclude a command to take before and after pictures and/or videos for anadditional task (e.g., a picture before a painting operation and apicture after the painting operation.

The robot may further be equipped with a sample gatherer and samplestorage compartment. The gathered samples may be analyzed by onboardsample analyzer (e.g., composition sensors), or delivered to a basestation for off-robot analysis. The robot can scrape and gather looseparticles, crackling, and/or spalling from designated areas of thestructure through a tool mounted on a tool arm of the robot. The toolmay include a vacuum to capture and store the scraped or looseparticles.

Still referring to FIG. 7, the operating instructions for performing adetecting, sensing, and/or analyzing task (704) may be for the purposesof identifying areas of the structure for the performance of anadditional task and times for the performance of designated tasks. Asdiscussed above, a sensor of the robot may be used to identify aspecific location of the structure (e.g., a crack, a localized stress,corrosion, paint defects, etc.) where a further operation (e.g.,cleaning, welding, painting, etc.) is desired. Further, the cameraand/or stress sensor may be used to determine when the structure isbeing used or is under load (e.g., when a train is crossing a bridge).For certain operations, such as stress measurement, cold-workingstructure material, heat treating structure materials, etc., it may bebeneficial to perform the operation while the structure is experiencingnormal stresses. For other operations, such as cleaning and painting,where debris or paint overspray may fall from the structure, it may bebeneficial to determine when the structure, or an area of the structureat risk of being hit or affected by the debris or overspray, is notbeing used or is not occupied so as not to damage objects or injureoccupants of the structure. For example, when performing a repaintingoperation of a bridge, the sensors and cameras can be used to determinewhen vehicles and/or people are not crossing the bridge so as not todamage or injure the people with overspray of the paint. Continuing withthe example, the robot may pause the repainting or cleaning operation ifthe robot determines that an object will enter an area affected bydebris or paint overspray until the object leaves the area. Stillfurther, feedback from the sensors may be used to identify potentialparticularly weak areas of the structure, areas of the structure at highrisk for corrosion, and/or areas of the structure at high risk for thedevelopment of cracks to be regularly inspected/and or treated. Sensorfeedback can be recorded at the same area of the structure overdifferent periods of time. The recorded data can then be stored in amemory of the robot and/or transmitted to another robot or to a basestation. The time correlated sensor readings can be used to calculatestructure degradation (e.g., physical degradation, paint degradation,etc.), to demonstrate crack development and migration, to calculatestructural and load models, to calculate estimated structural life, tocalculate fatigue life (e.g., based on crack development, crackmigration, crack depth, residual stresses, etc.).

Feedback from the sensors and/or cameras may be used during othermaintenance operations (e.g., welding, cleaning, painting, etc.). Thefeedback can be used to lengthen or shorten a treatment time for themaintenance task. For example, the sensor feedback may be used todetermine when the appropriate amount of peening has been performed in alater peening operation. Additionally, the sensor feedback can be usedto modify an on-going operation. For example, sensor feedback may beused to monitor internal stresses of the structure during crackmigration and make changes to the crack migration operation in responseto the sensor feedback.

The operating instructions may include an instruction for the robot toperform a painting task (705). Accordingly, the robot can be equippedwith a paint sprayer, a self-feeding paint roller, or another paintingtool. The painting task can correspond to a spot painting task, in whichthe robot roves the structure and repaints certain areas based on sensorfeedback. Alternatively the painting task can correspond to an areapainting task, in which an entire area of the structure (or the entirestructure) is to be repainted. The paint used by the robot may be aprimer, a latex-based paint, an anti-graffiti paint, an anti-climbpaint, an anti-fouling paint, an anti-corrosion paint, and/or aninsulating paint. As discussed above, cameras and sensors on the robotmay be used during a painting operation to select an appropriate time topaint and/or pause and restart the painting operation to avoid damagingobjects on the structure or injuring people occupying the structure.

The operating instructions may include an instruction for the robot toperform a cleaning task (706). The cleaning task may be performed priorto another task (e.g., the painting task of 705, the welding task of708, etc.). The cleaning task may involve the cleaning of the surface ofthe entire structure or a designated area of the structure (e.g., at anarea to be welded or repainted). The surface cleaning may remove aprotective coating (e.g., paint), an area of corrosion (e.g., a rustedportion of the structure), or a surface layer of the structure (e.g., toprepare the area of the surface layer for inspection or welding). Therobot performs the cleaning task through any number of tools attached toa tool arm of the robot. The robot may be configured to have an abrasiveblaster tool (e.g., a sand blasting tool) attached to the tool arm.Alternatively, the robot is configured with an abrasive grinding toolattached to the tool arm. In yet another alternative, the robot isconfigured with a brush attached to the tool arm.

Referring again to FIG. 7, the operating instructions may include aninstruction for the robot to perform a crack and dislocation migrationor prevention task (707). One way the robot may perform this task isthrough a peening operation. The robot may perform a peening operationto prevent the formation of cracks at an area of the structure.Generally, a peening operation works to relieve tensile stress in metaland replace the tensile stress with a compressive stress. Because cracksare more apt to form under tensile stress, the peening operation reducesthe risk of crack formation in the material. The peening operation maytarget the surface and/or the subsurface of the material of thestructure. The peening may be performed by repeatedly impacting thesurface of the structure to produce a compressive residual layer thatmodifies the structure of the material of the structure. The peeningoperation may be performed mechanically. To accomplish the mechanicalpeening operation, the robot may be equipped with a hammer to repeatedlystrike the surface of the structure. Alternatively, the robot may beequipped with a media blasting gun that emits shot (ceramic, steel,glass, etc.) at the structure. The peening operation may alternativelybe performed via a laser. Accordingly, the robot may be equipped with alaser to perform laser peening on the structure. Accordingly, the robotcan perform targeted hardening of an area of the structure by emitting alaser beam into the area of the structure. The laser beam is emitted inpulses that produce shockwaves through the structure at the area. Theshockwaves cause residual compressive stresses in the structure, whichmay improve the strength and/or fatigue life of the structure. The laserpeening may be performed after an energy absorbing coating (e.g., a darkcolored paint) is provided in a painting process (e.g., painting of705). The details of using a laser to perform a peening operation arediscussed in U.S. Pat. No. 6,288,353 to Dulaney et al., entitled “MOBILELASER PEENING SYSTEM,” dated Sep. 11, 2001.

The robot may be equipped to perform other area treating of structurematerials to prevent crack formation. For example, the robot may beequipped with an electric and/or magnetic field generator to performedlocalized heating of structure materials (e.g., inductive heatgeneration) for heat treatment purposes. As an additional example, therobot may be equipped with an ultrasound emitter. The ultrasound emittertransfers mechanical energy to the structural material to perform a workhardening operation similar to the peening operations discussed above.

The robot may also be equipped with a drill to be used in mitigating themigration of existing cracks. In such a configuration, the robot canstop the spreading of a crack by drilling at an edge of a crack. Thedrilled hole increases the radius of curvature of the crack therebyreducing the maximum stresses caused by the crack by spreading thestresses of a crack over a greater area. The structure strengtheningtask may be a crack dislocation and/or migration task. To perform thetask on a designated crack in the structure, the robot requires locationinformation that provides the location of the crack to the robot. Thelocation information may be provided with the operating instructions(e.g., an operator can instruct the robot to repair a specified crack ata specified location). Alternatively, the location information may begathered by the robot or another robot during a structure analysis viasensors or a camera (e.g., 704).

The operating instructions may include an instruction for the robot toperform a welding task (708). The robot may be configured to weldvarious metal structures. Depending on the configuration, the robotperforms arc welding with consumable or non-consumable electrodes,oxyfuel gas welding, tungsten inert gas welding, friction stir welding,resistance welding, laser beam welding, electron beam welding, or a formof solid-state welding. The operating instructions may instruct therobot to insert filler material into located cracks by performing welds.The filler material may be provided from a wire of metal, which is usedto fill small cracks and holes, or may be a larger, custom plate, whichis welded into place to fill larger gaps in the structure's material.The robot may be instructed to perform localized welding or meltingoperations to resurface material after a cleaning operation (e.g.,cleaning performed in 706) and/or prior to a painting operation (e.g.,painting performed in 705). The robot may also perform the welding taskto relieve, create, and/or control stress levels in the surface andsubsurface of the structure.

The operating instructions may include an instruction for the robot toperform a tool change (709). As discussed above with respect to robot200, robot 300, robot 400, and robot 500, the robot may include at leastone tool arm. The tool arm can be equipped with a variety of tools andsensors. Some operating instructions may call for the performance of avariety of tasks. Accordingly, the robot may need to change tools duringperformance of the operating instructions if a greater number of toolsis required than tool arms available. The spare tools and equipment maybe stored on the robot. In such an arrangement, the robot performs thetool change at the worksite. Alternatively, the spare tools andequipment may be stored on another robot. In this case, the robot willcommunicate with the another robot to coordinate the tool change. In yetanother alternative, the spare tools and equipment may be stored at aspecific location on or near the structure (e.g., a robot storage space,the base station, etc.). In such a setup, the robot roves to the storagelocation to perform the tool change, and then the robot returns to theworksite to perform the task.

The operating instructions may include an instruction for the robot toperform a recharging operation (710). During execution of the operatinginstructions, the robot may need to recharge its batteries or the toolbatteries. The recharging operation may be automatically triggered bythe controller of the robot if battery levels fall below a level ofcharge. The robot may perform the recharging operation in a variety ofways. In some arrangements, the robot is equipped with a solar panelcapable of recharging the robot's batteries. In such an arrangement, therobot moves to an area of the structure such that the solar panels arepositioned in sunlight. In other arrangements, the robot instructs apower supply robot to provide a charge. The power supply robot isequipped with power storage devices (e.g., batteries, capacitors, etc.)that can be used to recharge the batteries of the robot. In anotheralternative charging scenario, the robot can recharge its batteries byroving to a charging station. The charging station provides grid powerto the robot through inductive charging (wireless charging) or a wiredelectrical connection. In another arrangement, the robot can receive acharge from another robot.

The operating instructions may include an instruction for the robot tocommunicate with other robots (711). As discussed above, many tasks canutilize multiple robots. The multiple robots may cooperate in working,sharing data, and passing data to the base station (e.g., passing datato servers). The robots may perform multiple tasks in a coordinatedsequence (e.g., a first robot cleans an area of a surface of thestructure, a second robot welds the area, and a third robot paints thearea). Alternatively, robots may perform the same task in parallel(e.g., multiple robots inspect different areas of the same structure toperform a structure-wide inspection faster than a single robot canprovide). Still, in an alternative setup, robots may perform independenttasks simultaneously (e.g., a first robot inspects, a second robotwelds, a third robot carries additional tools and supplies, a fourthrobot provides recharging services to the other robots, etc.). Stillfurther, multiple robots can perform the same task at the same time. Forexample, while fixing a deep crack in a thick material, a first robotcan heat the material from a first side while a second robotsimultaneously heats the same material from an opposite side. In anotherexample of two robots performing the same task at the same time, tworobots may be positioned on opposing ends of a turnbuckle that needs tobe shortened or lengthened, and the distance between the two robots maybe monitored to determine when the turnbuckle has be adjusted to anappropriate length. In another alternative, multiple robots may eachcarry or support a different portion of a component, such as a tie rodor a cable, that is not capable of being supported or carried by asingle robot. In each arrangement, it may be necessary for the variousrobots to communicate with each other and to pass coordinatedinformation on to the base station or to a server. Accordingly, therobots each are equipped with wireless transceivers capable oftransmitting and receiving instructions directly from other robots.Alternatively, inter-robot communications are coordinated through a basestation such that an instruction sending robot first sends aninstruction to the base station, where the instruction is processed,automatically by a computing system or by a human operator, and relayedto the recipient robot.

Although the above discussion primarily focuses on bridge cleaningrobots (e.g., robots 103), it should be understood that the abovediscussed systems and methods may be used on non-bridge structures. Forexample, robots 103 may be used to inspect, clean, and repair structuressuch as power plants, commercial skyscrapers, residential buildings, andoff-shore oil platforms, to recite several examples. The robots may beused on exterior surfaces of structures, interior surfaces ofstructures, or within hollow structures. Further, the above discussedsystems and methods may be applied to inspect, clean, and repair otherobjects and devices, such as airplanes, spacecraft, boats, trains,automobiles, and other devices. Any sort of object in need ofinspection, repair, and/or cleaning may utilize the above discussedsystems and methods.

The construction and arrangement of the systems and methods as shown inthe embodiments are illustrative only. Although only a few embodimentsof the present disclosure have been described in detail, those skilledin the art who review this disclosure will readily appreciate that manymodifications are possible (e.g., variations in sizes, dimensions,structures, shapes and proportions of the various elements, values ofparameters, mounting arrangements, use of materials, colors,orientations, etc.) without materially departing from the novelteachings and advantages of the subject matter recited. For example,elements shown as integrally formed may be constructed of multiple partsor elements. The elements and/or assemblies of the enclosure may beconstructed from any of a wide variety of materials that providesufficient strength or durability, and in any of a wide variety ofcolors, textures, and combinations. Any embodiment or design describedherein not necessarily to be construed as preferred or advantageous overother embodiments or designs. Accordingly, all such modifications areintended to be included within the scope of the present inventions. Theorder or sequence of any process or method steps may be varied orre-sequenced according to alternative embodiments. Anymeans-plus-function clause is intended to cover the structures describedherein as performing the recited function and not only structuralequivalents but also equivalent structures. Other substitutions,modifications, changes, and omissions may be made in the design,operating conditions, and arrangement of the preferred and otherembodiments without departing from scope of the present disclosure orfrom the spirit of the appended claims.

The present disclosure contemplates methods, systems, and programproducts on any machine-readable media for accomplishing variousoperations. The embodiments of the present disclosure may be implementedusing existing computer processors, or by a special purpose computerprocessor for an appropriate system, incorporated for this or anotherpurpose, or by a hardwired system. Embodiments within the scope of thepresent disclosure include program products comprising machine-readablemedia for carrying or having machine-executable instructions or datastructures stored thereon. Such machine-readable media can be anyavailable media that can be accessed by a general purpose or specialpurpose computer or other machine with a processor. By way of example,such machine-readable media can comprise RAM, ROM, EPROM, EEPROM, CD-ROMor other optical disk storage, magnetic disk storage or other magneticstorage devices, or any other medium which can be used to carry or storedesired program code in the form of machine-executable instructions ordata structures, and which can be accessed by a general purpose orspecial purpose computer or other machine with a processor. Wheninformation is transferred or provided over a network or anothercommunications connection (either hardwired, wireless, or a combinationof hardwired or wireless) to a machine, the machine properly views theconnection as a machine-readable medium. Thus, any such connection isproperly termed a machine-readable medium. Combinations of the above arealso included within the scope of machine-readable media.Machine-executable instructions include, for example, instructions anddata which cause a general purpose computer, special purpose computer,or special purpose processing machines to perform a certain function orgroup of functions.

Although the figures may show a specific order of method steps, theorder of the steps may differ from what is depicted. Also two or moresteps may be performed concurrently or with partial concurrence. Suchvariation will depend on the software and hardware systems chosen and ondesigner choice. All such variations are within the scope of thedisclosure. Likewise, software implementations could be accomplishedwith standard programming techniques with rule based logic and otherlogic to accomplish the various connection steps, processing steps,comparison steps, and decision steps.

What is claimed is:
 1. A system for maintaining a structure, comprising:a first robot, the first robot including a first robot body, a firstrobot tool arm coupled to the first robot body, a first robot sensorcoupled to the first robot body, a first robot drive system configuredto allow positioning of the first robot along the structure, includinginverted positioning and vertical positioning, a first robot transceivercoupled to the first robot body, and a first robot controller coupled tothe first robot body; a second robot, the second robot including asecond robot body, a second robot drive system configured to allowpositioning of the second robot along the structure, a second robottransceiver coupled to the second robot body, and a second robotcontroller coupled to the second robot body; and a base station incommunication with at least one of the first robot via the first robottransceiver or the second robot via the second robot transceiver;wherein the first robot is configured to autonomously perform amaintenance task on the structure; wherein the second robot isconfigured to autonomously provide a support service to the first robotduring the maintenance task; and wherein the first robot is configuredto electronically communicate with the second robot.
 2. The system ofclaim 1, wherein the second robot further includes a second robot toolarm coupled to the second robot body.
 3. The system of claim 1, whereinthe second robot drive system is configured to allow invertedpositioning and vertical positioning of the second robot.
 4. The systemof claim 1, wherein the base station is configured to send signals tothe second robot via the first robot.
 5. The system of claim 1, whereinthe second robot is configured to send signals to the base station viathe first robot.
 6. The system of claim 1, wherein the second robotincludes a storage compartment housing a supply necessary for completionof the maintenance task.
 7. The system of claim 6, wherein the supply isa tool.
 8. The system of claim 7, wherein the second robot is configuredto mount the tool on a first tool arm of the first robot.
 9. The systemof claim 6, wherein the supply is a consumable fluid.
 10. The system ofclaim 9, wherein the consumable fluid is paint or cleaner.
 11. Thesystem of claim 1, wherein the first robot and the second robot arecoupled to each other via an optical fiber.
 12. The system of claim 1,wherein the second robot includes a supplemental power source and acharging port.
 13. The system of claim 12, wherein the second robot isconfigured to provide a charge to a power source of the first robotthrough the charging port.
 14. The system of claim 1, wherein thesupport service includes locating an area of the structure to berepaired, and the maintenance task is repairing the area of thestructure.